The type of hard disk that typically connects to a USB or Thunderbolt port on the system unit.

The type of hard disk that typically connects to a USB or Thunderbolt port on the system unit is known as an External Hard Drive. Here are the steps to connect it:

1. Locate the USB or Thunderbolt port on your system unit. This is usually found on the sides of laptops or the back of desktop computers.

2. Connect one end of the USB or Thunderbolt cable to the external hard drive.

3. Connect the other end of the cable to the USB or Thunderbolt port on your system unit.

4. Your computer should automatically detect the external hard drive. If it doesn't, you may need to manually configure it through your system settings.

5. Once detected, you can start using your external hard drive to store and access files.